If it weren't for Steve Jobs, Apple may have eventually died out at the turn of the century. However, if it weren't for Microsoft (and Bill Gates, mostly), Apple may still have died out with Steve Jobs at the helm - $150 million in cash for non-voting stock and an agreement to continue selling Office for the Mac for 5 years (in exchange for dropping the lawsuit Apple had against Microsoft - it wasn't all altruism, or perhaps none at all) was ultimately what put Apple on their trajectory. Office for the Mac was important then (and Steve Jobs knew it, hence why he wanted the 5 year agreement to continue making it available on Apple's platform), probably more so than it is now. Also, there is rumored to have been much more cash exchanged (the schedule B portion of the deal that was secret) than the $150 million reported, as Apple lost over a billion or so dollars over the previous two years, and had another billion lost on revenues (and reported only $1.2 billion in cash holdings at the time) and yet ended in the black and maintained their investments (and even started accumulating cash) very quickly after that point, without a huge uptick in sales to account for it - interesting indeed, and it would still have been nothing for Microsoft (or even Bill Gates himself) at the time to do without affecting anything in either's lives. Also, Microsoft got access to Apple's labs and R&D over that same 5 year span, so it seems like both companies' cultures were affected positively by the deal, regardless of what it ultimately was behind closed doors.
Viewed in the lens of Apple as a hardware company, and Microsoft a software one (mostly, anyway), it makes sense Microsoft would write Office for the Mac, as that's what Microsoft does. It's a little odd because you'd think they'd want to push Office licenses for Windows instead of the Mac, but I doubt it makes a huge difference or impact on Windows' dominance in the market. It makes money, and probably isn't a threat to Microsoft's market position(s) at all; thus, as long as that stays true, Microsoft will gladly take money from whomever is willing to give it to them - be it a Mac user or a Windows user
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